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BesselK[n, z]
gives the modified Bessel function of the second kind K_n(z).
  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • K_n(z) satisfies the differential equation z^2​y^(′′)+z​y^′-(z^2+n^2)​y=0.
  • BesselK[n, z] has a branch cut discontinuity in the complex z plane running from -∞ to 0.
  • For certain special arguments, BesselK automatically evaluates to exact values.
  • BesselK can be evaluated to arbitrary numerical precision.
  • BesselK automatically threads over lists.
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